Well, to be fair, I'm only deriving that plot point from this one line on page 228:
"Her [Lyta's] death was another thing he [Garibaldi] owed Bester for."
Garibaldi could be referring to Bester's role in the telepath war in very general terms. Speaking of which, what does the script you're looking at say about the whole thing?
And thanks for the heads up on the coupons. I've only been able to find the 5 dollar off one at the moment, though.